Vaccines have recently been shifting from a live vaccine to an inactivated vaccine (all particles, a component, a vaccine, and the like) with the aim to improve the safety. The use of the inactivated vaccine reduces a risk such as infection, but on the other hand, may sometimes invite lowering of an immunologic response. In order to supplement the lowering of the immunologic response, the vaccine is often administered together with an adjuvant.
As a method for administering the adjuvant, subcutaneous administration, transdermal administration, transmucosal administration, and the like are known. The transdermal administration and the transmucosal administration are characterized by excellent convenience and safety, compared to the subcutaneous administration using an injection.
Patent Literatures 1 and 2 describe adjuvants for transdermal or transmucosal administration, which contain at least one member selected from aliphatic alcohols, free fatty acids and fatty acid derivatives but do not contain a specific bivalent unsaturated carboxylic acid ester. Patent Literature 3 describes an adjuvant for transdermal or transmucosal administration, which contains one or more members selected from the group glycerol, propylene glycol, polyethylene glycol, and triacetin, which are polyhydric alcohols or derivatives thereof.